Hydrodynamic Performance And Comprehensive Optimization Analysis Of Green Energy Unmanned Catamaran

In the case of energy crisis and serious pollution of ships,how to do a good job of energy conservation and emission reduction of ships has become a topic of concern for all mankind.With the continuous development of green ship technology,the application of clean energy represented by solar energy and wind energy in ships is the most representative.By studying various technical solutions or design concepts of using clean energy on ships,it is found that using single energy is not the best way.According to different ship types,performance,structure,general layout,power system and other factors,the comprehensive utilization of various energy sources has become an important development direction of new energy ships.In this paper,a kind of green energy double body unmanned boat is studied on the comprehensive optimization of hydrodynamic performance and boat type.The multidisciplinary design optimization method can effectively improve the design quality,and finally get the overall optimal solution.So it has broad development space and practical significance to apply the multidisciplinary design optimization method to the design field of unmanned boat.The specific research work of this paper is as follows:(1)Based on the residual resistance coefficient curves of four parent ships and the correlation curves of ship main dimensions,ship type coefficients and main parameters,the relevant database is constructed by the method of response surface fitting,including coefficient,parameter formula,which can provide data support for relevant research.A set of database which is most suitable for this paper is recommended through calculation and comparison for many times,so as to lay a foundation for the construction of optimization mathematical model.(2)This paper studies and analyzes the rapidity,maneuverability,seakeeping,stability,solar energy and sail system,and constructs the appropriate sub objective function in turn.Under certain constraint conditions,a set of design variables is found,so that the larger the value of the objective function is,the better.Then,according to the influence degree,the weight of the subsystem is set,and finally,the total objective function of comprehensive optimization is combined in the form of power index product.(3)Select three kinds of intelligent optimization algorithm,compare and analyze the advantages,disadvantages and application scope of each algorithm.In order to ensure the efficiency of the algorithm,layered and parallel strategies are introduced to improve the algorithm.Combined with the mathematical model of integrated optimization,a set of software for integrated optimization design of unmanned catamaran is adapted based on C#language and Microsoft Visual Studio platform.Then the genetic algorithm,chaos algorithm and particle swarm optimization algorithm are discussed and calculated respectively,and the optimal parameters of each algorithm are obtained.(4)In view of the shortcomings of the algorithm,on the basis of the growth mechanism genetic algorithm,the hierarchical strategy is adopted to continue the optimization.It is found that the optimization effect of the hybrid algorithm is higher than that of the single genetic algorithm,in which the genetic + particle swarm optimization algorithm is the best.In addition,it is found that the use of parallel strategy can effectively improve the optimization effect of the algorithm,and get better optimization results when parallel multiple sensitive variables and multiple parallel computing.Through many times of optimization calculation,the optimal main dimensions and hull parameters under different Froude numbers are finally obtained,which can provide reference for hull design.(5)According to the optimization results,the propulsion and control system is designed,the solar energy and sail system are theoretically analyzed and preliminarily designed and calculated,the superstructure is designed after the utilization of green energy is considered,the model is built according to the model line diagram and optimization results of the parent ship,and finally the design and manufacture of the catamaran unmanned boat model is completed.(6)Finally,water tightness test,rapidity test,maneuverability test and seakeeping test are carried out to verify the feasibility of each system design and the better performance of the boat model designed in this paper.Finally,based on the idea of system identification,the roll and pitch system identification software of the catamaran unmanned boat is adapted,and then the identification calculation is carried out through the data of roll and pitch test.Based on the identification results,it is found that the error between the test data and the identification data is small,which shows that the identification software is reliable,and the best roll and pitch motion prediction formula is finally obtained,which can reduce the adverse effect of roll or pitch motion influence.